Gender and Alcoholic Subtypes.

Although women generally have been subjects of alcohol research less often than men, gender can be used as a defining characteristic in subtyping schemes. Whether the sexes actually differ in aspects of their alcoholism, such as in etiology and degree of severity, however, is not known. Analyzing a sample of male and female alcoholics using several different statistical methods, the researchers found that men and women with either a severe or mild form of alcoholism differed little in their character profiles and etiologies. Women and men with moderately severe alcoholism, however, tended to differ with respect to co-occurring psychopathologies (e.g., depression or antisocial personality) and the degree to which they drank to relieve other conditions (e.g., boredom). These findings suggest that different forms of alcoholism treatment may be most effective for men and women with moderately severe alcoholism. However, as is the case with any subtyping scheme, this conclusion cannot be applied to the general population without further research.


R esearchers and practitioners
into smaller groups of alcoholics with tween male and female alcoholics, and have long recognized that similar characteristics-is one method gender has surfaced as a defining char alcoholics 1 are not all alike; of bringing order to the variability with acteristic in many major subtyping rather, they vary along numerous di in this population. schemes. By studying gender differ mensions, including their family histo In general, women have been studied ences among alcoholics, researchers ries, their stated reasons for drinking, less often than men in all areas of alco have compiled traits and circumstances and their personality characteristics. hol research. Nevertheless, scientists that tend to be more common for men or These differences have important im have found that differences exist be for women (see Lex 1990). Subtyping plications for understanding the etiology formulations potentially can provide a (i.e., development) of alcoholism as simple way to summarize gender well as for prevention, intervention, FRANCES K. DEL BOCA, PH.D., formerly related similarities and differences and treatment efforts. Subtyping-that an assistant professor in the Depart among alcoholics. is, dividing a large group of alcoholics ment of Psychiatry, University of Con necticut Medical School, Farmington, This article presents an overview • In terms of subtypes, what are the important similarities and differ ences between the sexes?
• How can subtyping research add to the understanding of how men and women differ in their development of alcohol problems?
• How might findings from subtyping research affect intervention and treatment for men and women?
• What are the limitations of existing subtyping research?

GENDER IN SUBTYPE FORMULATIONS
The content of subtype profiles often depends on the range of attributes that researchers decide to consider when making distinctions among alcoholics. Two prominent subtyping studies (Schuckit et al. 1969;Cloninger 1987) brought gender differences into con sideration and expanded on earlier typological approaches that had tend ed to emphasize differences in drink ing patterns.

Early Subtypes
In one of the earliest studies of gender and alcoholism subtypes, Schuckit and his colleagues (1969) described two major variations in female alcoholism, primary and secondary. Primary alco holics were women whose damaging drinking patterns developed apart from any other psychological disorders, and secondary alcoholics were women for whom alcoholism developed after they experienced either depression or anxi ety (i.e., affective disorders). This dis tinction, which has become somewhat controversial, is consistent with numer ous studies that have found depression and anxiety to be more prevalent in female than in male alcoholics (for re view, see Hesselbrock 1991). Schuckit's scheme was the first to focus attention on women and concomitant mood dis order (e.g., affective disorder).
In what was to become one of the most influential approaches to subtyp ing alcoholics, Cloninger (1987) pro posed a subclassification of two types: type II ("malelimited") alcoholics, who experienced a more severe form of alco hol abuse and had fathers who exhibited both criminal behavior and severe alco hol abuse, and type I ("milieulimited") alcoholics, whose less severe alcohol ism was less often associated with fam ily history. Bohman and colleagues (1981) analyzed women from the Clon inger study and placed women in a single category, type I. This partitioning was based on differences in the alco holics' temperaments (e.g., whether their actions were driven by their desire for reward or avoidance of harm) rather than their psychopathology. In addition to drawing attention to alcoholic men, Cloninger's work was among the first to consider the genetic contribution in alcoholism subtyping. Type II was characterized by genetic factors inde pendent of environmental influences, whereas type I was influenced by both genetic and social/situational factors (e.g., social norms regarding drinking). Historically, differing social prescrip tions for drinking have existed for each gender, wherein more sanctions have been applied to women than to men. Thus, Cloninger's recognition of the potential importance of nongenetic factors in the etiology of alcoholic subtypes is likely to have implications for understanding the differential de velopment of alcohol problems in both women and men.

The Type AType B Subtype
Researchers have arrived at another classification-the type Atype B subtype-that addresses alcoholism in both men and women. Type A and type B alcoholics are defined in terms of a broad range of factors, including psy chopathology and family history of alcoholism, and are grouped according to the severity of their disorder. These two subtypes were derived from studies using a statistical method (i.e., cluster analysis) that classifies individuals into groups (i.e., clusters) based on their similarities with regard to the attributes selected for analysis   1). Study participants were recruited from three treatment facilities more than a decade ago, and intensive followup evaluations were performed both 1 year and 3 years after the initial treatment.
The RiskSeverity Distinction. Analyses produced a useful set of two subtypes (type A and type B) that dif fered significantly in terms of 16 of the 17 attributes. Type A alcoholics were characterized as having a low risk for developing alcoholism; those who did develop the disease did so at a low level of severity. In contrast, type B alcoholics had more risk factors, such as a family history of alcoholism, a younger age of onset, and early con duct problems (e.g., getting into fights or stealing). Type B alcoholics also ex hibited more severe dependence symp toms, such as tolerance and withdrawal; alcoholrelated consequences, includ ing liver disease and job loss; and psy chopathologies, such as depression and anxiety. Separate analyses for each sex produced the basic type Atype B dis tinction (see Babor et al. 1992). Alco holic men were disproportionately categorized, however, as type B (53 percent of the men compared with 38 percent of the women), whereas women were more likely to be classified as type A (62 percent of the females versus 47 percent of the males).
The type Atype B typology has been replicated in several studies using different samples and somewhat different measures (Litt et al. 1992;Brown et al. 1994;Schuckit et al. 1995). In addition, researchers consistently have found that males and females dif fer in their distribution among the two subtypes: Males are more prominent within the type B category (e.g., Brown et al. 1994;Schuckit et al. 1995).
The two subtypes also have proven useful for predicting which group has the best chance of recovery from alco holism. Type A alcoholics generally exhibit better outcomes . Finally, and perhaps most im portant from a practical perspective, this typology may help clinicians match patients to specific treatments that will be the most effective for their type of alcoholism (Litt et al. 1992) (for an update of findings regarding the type Atype B distinction, see the article by Allen, pp. 24-29). The type Atype B distinction implies quantitative, as well as qualitative, differences among alco holics. That is, in addition to indicating that two categories of alcoholics exist with characteristic profiles, this formu lation suggests that alcoholics differ along a general dimension or continuum characterized as low risklow severity at one end and high riskhigh severity at the other. Several other investigations have confirmed this finding (e.g., Good win et al. 1994). Women and men may simply fall at different extremes along this dimension, or important differences may exist between the genders in terms of subtype profiles.
As demonstrated by the type Atype B typology, when researchers consider a broad range of attributes while sub typing alcoholics, they obtain cate gories that apply to both genders. These subtypes are primarily distinguished in terms of risk for and severity of al coholism. At the same time, however, the number of women or men within each subtype, together with the results of research comparing alcoholic men and women, suggests that important gender differences may exist within each subtype. These differences may be specific characteristics that have etiologic and treatment significance for both men and women.

Gender Similarities and Differences Within Each Subtype
When a study considers gender, a different subtyping solution may be reached. To examine more fully the interaction between gender and the type Atype B distinction, Del Boca (1994) conducted several secondary analyses using the data set from the typology study reviewed earlier (i.e., Babor et al. 1992). Men and women within each subtype were first com pared using the subtype classifications produced in the original study by Babor (Del Boca 1994). The results of these  Babor et al. 1992. comparisons, summarized in table 1, show that the profiles of type B males and females are relatively similar, whereas women and men categorized as type A differ. As indicated in table 1, the type B men and the type B women differed significantly on only 4 of the 17 at tributes used to define the typology. The men reported longer drinking histories, more severe lifetime conse quences, and more symptoms of anti social personality disorder 2 than did the type B women; in contrast, women in this category showed significantly higher levels of a family history of al coholism. Despite expected differences in body size and metabolism, the sexes did not differ in terms of the quantity of alcohol consumed or dependence 2 Antisocial personality disorder is a pattern of irre sponsible and antisocial behavior beginning early in life and continuing through adulthood. severity, nor were there differences in symptoms of affective disorders. In contrast, substantial gender dif ferences were evident within the type A group for 13 of the 17 comparisons. On average, the type A male alcoholics reported that they began drinking at an earlier age and were found to have higher scores on a measure of person ality that tended to distinguish alco holics from nonalcoholics; however, as in the type B category, type A female alcoholics exhibited higher levels of family history of alcoholism. Men in this subtype reported drinking greater quantities of alcohol than their female counterparts but reported less drinking in response to stress and other nega tive states (e.g., feeling sad) and less use of tranquilizing drugs. Although the men had longer drinking histories, they appeared to suffer fewer physical and social consequences and to have fewer medical complaints than did the women. Perhaps most striking were the differences in psychopathology. As in the type B category, type A men ex hibited more symptoms of antisocial personality; at the same time, however, the women showed significantly more depression and anxiety.
This comparison suggests two tenta tive conclusions regarding gender and alcoholic subtypes. First, it appears that the more severe form of alcohol ism, type B, is not male limited, in contrast to Cloninger's type II alco holism. Although a smaller proportion of the women fell into this category, those who did may be comparable to the men in terms of a variety of risk and severity factors. Second, those men and women categorized as type A al coholics appeared to differ in important ways, as previously described. Most notably, women in this group exhibited higher levels of affective disturbance (e.g., depression and anxiety); reported more severe medical and social con sequences of their alcohol use; and appeared to selfmedicate, using tran quilizers as well as alcohol (table 1).

A Second Look at Gender and Subtypes
To further explore gender in relation to subtypes, additional analyses were performed on the Babor study data using the statistical techniques men tioned earlier (Del Boca and Hessel brock 1995). Although the twocluster solution subtypes (i.e., type Atype B) effectively represented the study sam ple in terms of risk and severity, new groups were derived to explore whether meaningful, genderrelated subtypes would emerge. Using the new analysis, researchers discovered that dividing the sample into four clusters also pro duced a functional solution. Differences between the men and women in the new typology were most evident in two of the groups. Table 2 presents profiles of the four new subtypes sug gested by this analysis.
The largest subtype, containing ap proximately onethird of the cases (28 percent of the men in the study popu lation and 39 percent of the women), was characterized by relatively low risk and severity and was labeled as such. A second group contained equal proportions of men and women (22 percent from each group) and included those cases with the most pervasive family histories of alcoholism and the lowest age for first alcohol use. This subtype, labeled "high riskhigh sever ity," was characterized by conduct problems, illicit drug use, and antiso cial personality.
The two intermediate subgroups were more gender specific. The "in ternalizing" subtype, which was la beled as such because of the ways in which its members expressed feelings and responded to their environments, included 32 percent of the women in the study population and only 11 per cent of the men. This group comprised depressed and anxious alcoholics who reported often using alcohol to relieve anxiety or boredom (i.e., relief drink ing). Members of this subtype were severely alcohol dependent and had medical or physical problems resulting from alcohol use. In addition, they showed only a moderate family history risk. The other group, the "externaliz ing" subtype, was predominantly male (containing 38 percent of the men ver sus 7 percent of the women), thereby indicating a gender bias. Members of this group also reported only a moder ate family history of alcoholism. They did, however, report high levels of al cohol use, social consequences, and antisocial personality.
Members of the four groups also were compared in terms of age, and sig nificant differences were found. Those in the high riskhigh severity subtype were younger than those in the other three groups (mean age = 27 versus 42 years). Thus, the division of patients into the first group appears in part to have been related to their age and their druguse practices (discussed below).
Comparisons among the four groups both 1 year and 3 years later revealed significant differences. For example, both the high riskhigh severity group and the externalizing group tended to show poor outcomes relative to the other two subtypes. The two groups also were characterized by symptoms of antisocial personality disorder, which, not surprisingly, are associ ated with poor prognosis.

IMPLICATIONS FOR ETIOLOGY
The fourgroup typology described above suggests that several pathways may lead to the development of alco hol problems in both women and men. These subtypes do not directly address the issue of etiology; nevertheless, with other research findings, they provide a basis for speculation about the course of alcoholism for different groups of women and men.
Consistent with recent research, the typology findings suggest that a family history of alcoholism predis poses women, as well as men, to a wide range of problems, one of which is alcoholism. The high riskhigh sever ity group is characterized by high lev els of risk factors, including a strong family history of alcoholism, that are evident at a relatively young age in both Alcoholic women are more likely than alcoholic men to report prior histories of physical and sexual abuse genders and result in similar character istics for both men and women. As Hill and colleagues (1994) suggest, how ever, the progression toward alcohol problems may change, perhaps as a result of environmental factors (e.g., childhood upbringing). Such factors appear to dilute the effect of a family history of alcoholism on the later de velopment of alcoholism. Thus, it is possible that differing childhood en vironments for males and females at risk for developing alcohol problems can alter whether and how they develop these problems later in life. The two subtypes that appear to be gender related (i.e., internalizing and externalizing) share some characteris tics; these attributes suggest that the etiologies among these groups may depend less on inherited characteristics than do the disease origins of the high riskhigh severity subtype. The inter nalizing and externalizing groups are equivalent in terms of family history (i.e., both have moderate levels), degree of alcohol dependence, and alcohol related consequences. The predomi nantly male, externalizing subtype, however, shows more early signs of problem behavior, including con duct problems, and earlier age of on set for problem drinking. In contrast, the internalizing subtype exhibits higher levels of depression, anxiety, and relief drinking. The characteristics are not entirely gender specific. They do, how ever, mirror gender differences-such as a higher incidence of depression and anxiety among women-commonly reported for nonalcoholic populations. The subtype differences also bear a clear correspondence to traditional gen der roles (see Del Boca 1994), which reflect social norms about what is thought to be the "appropriate" behav ior of men and women. Traditionally, the social "shoulds" for men within our culture emphasize assertive, task oriented behavior, whereas those for women prescribe emotional expressive ness and deference. The extremes of these behaviors can result in the types of mood disorders characteristic of these two alcoholic subtypes.
Evidence from studies of adolescents supports differing etiologies for males and females, suggesting that adolescent girls who are more involved in AOD use than their peers have characteristics reminiscent of the internalizing sub type. Likewise, adolescent boys who use AOD's have profiles similar to the externalizing subtype (Del . Thus, young people's responses to their environment, which appear to be connected to their gender, may predict their development of al cohol problems. The moderate levels of early risk factors found in the two genderrelated subtypes, together with the parallels to conventional gender roles, suggest that the development and expression of alcohol problems in the two groups depend on sociocultural factors (e.g., differing social expectations for wom en and men or differential approval of drinking by men versus women) rather than an inherited predisposition. This observation suggests an etiology for women in the internalizing group. De spite the current acceptability of a wider range of roles for women in American society, assertiveness among women is still discouraged. Thus, females might be expected to internalize problems and to selfmedicate with alcohol to a greater degree than males; higher lev els of negative affect and guilt as a result of drinking may set the stage for an alcohol consumption pattern that could result in alcoholism for the internalizing subtype. Similarly, the greater acceptability of aggressiveness and alcohol use among males may con tribute to the pattern observed in the externalizing subtype.

CONSIDERATIONS FOR INTERVENTION AND TREATMENT
Numerous articles have been published summarizing how women and men seek treatment for alcoholism and ex amining gender differences in treatment outcome (e.g., Stobar and Annis 1996;Jarvis 1992). In addition to these stud ies, subtyping research may be espe cially useful for designing intervention and treatment programs.
Some suggestions for alcoholism treatment that may be gleaned from prevention, treatment, and typology research are as follows: • Both gender and the type Atype B distinction currently are under in vestigation as the potential bases for patienttreatment matching in Project MATCH, a large, multisite, clinical trial examining whether matching clients with certain attri butes to particular treatment modal ities improves outcome (see Project MATCH Research Group 1993). The results of this study will pro vide empirical evidence regarding the usefulness of treatment match ing based on gender or on subtypes that distinguish people specifically on the basis of risk and severity.
Although this straightforward ap proach may prove promising, the foursubtype formulation presented earlier suggests that matching may require a more complex strategy that considers gender, in combina tion with risk and severity, for ef fectively treating the whole range of the alcoholic population.
• The profiles of the most and least severe subtypes in the fourgroup scheme indicate more similarities than differences between the sexes in terms of treatment needs. For ex ample, choice of a particular inter vention or treatment could be based on the severity of alcohol problems evidenced by the individual. Low intensity (e.g., outpatient) treatment might be used for those in the low risklow severity group, whereas more intensive (e.g., day hospital or inpatient) treatment may be ap propriate for the high riskhigh severity group. Welldesigned treatmentoutcome research in volving both female and male al coholics is needed to empirically validate the use of specific treat ment approaches for these two groups. Members of the internaliz ing and externalizing subtypes, how ever, differ in terms of their concomitant psychopathology and may differentially benefit from programs designed to address their range of symptoms. In these two groups, affective disorders should be addressed as comorbid diag noses. For example, copingskills training could be used to address depression and anxiety. As sug gested by prior matching research, those in the externalizing group also may benefit more from coping skills therapy than from less structured treatments, such as insightoriented group therapy (Litt et al. 1992). 3 • Other research proposes additional considerations in terms of address ing the different needs of women and men. Women may require more ancillary services (e.g., child care) and may prefer samesex therapists, although the empirical evidence in support of this preference is mixed. Finally, other experiences and prob lems that may require special ser vices are linked to gender but not addressed in the subtype literature. Alcoholic women, for example, are more likely than alcoholic men to report prior histories of physical and sexual abuse that could affect their success in treatment (e.g., Windle 1995).
3 Copingskills therapy is intended to teach alcoholics specific behavioral skills that help them cope with their urges to drink. Insightoriented therapy usually in volves group sessions and is intended to help alco holics achieve insights into their reasons for drinking.

Prevention Considerations
In terms of prevention and early inter vention, research suggests that female adolescents with AODrelated problems often are referred to treatment later than their male counterparts and at a time when their problems are more severe . In part, this delay may result from the tendency of people to presume that girls are less likely to become involved in AOD use. It also may stem, however, from the tendency of young women to internalize their problems, making their alcohol abuse much less visible than that of their male counterparts. Parents, teachers, and others who interact with adolescents should be trained to identify "internal izers" who are predisposed to alcohol related problems (e.g., these adoles cents often are withdrawn or moody) as well as those who have more obvi ous behavioral problems.

LIMITATIONS OF EXISTING RESEARCH
As evidenced by this issue of Alcohol Health & Research World, consider able ongoing research on alcoholic subtypes exists that has important practical as well as theoretical implica tions. Although research on alcoholic women has increased in recent years, the role of gender in relation to alco holic subtyping is not often studied. Consequently, the implications of the analyses reported here are somewhat speculative. More research is needed to understand the manner in which genetic and sociocultural factors in fluence drinking patterns and the de velopment of drinking problems in men and women. In addition to the limitations of direct empirical evidence, certain ca veats regarding subtyping research in general should be noted. The analytical methods used to identify subtypes (e.g., cluster analysis) are primarily descrip tive in nature and intended to uncover typological structure in empirical data. Although the solutions that these meth ods produce can aid in the develop ment of subtyping theory and inform the design of prevention and treatment programs, the results are primarily of heuristic (i.e., educational) value. The subtypes suggested by such methods reflect only the characteristics of the sample studied and the investigator's choice of relevant personal attributes. Thus, researchers should avoid the ten dency to construe subtypes as more than a theoretical construction. Specific subtyping methods are particularly well suited to certain tasks; different approaches (e.g., two versus four clus ters for the same study population) are not necessarily competing representa tions of "reality." The usefulness of any particular solution will depend on the investigator's purpose (for further discussion of this general point, see Del Boca 1994).
A final cautionary note concerns the research sample used in the analyses described in this article. Although the sample is large and diverse with a high proportion of women, and the results are consistent with those from other studies, the profiles that have emerged probably reflect the characteristics used to define the typology as well as the ef fect of data artifacts such as age. For example, abuse of drugs other than alco hol was more characteristic of younger adults at the time the data were col lected, and this pattern may be reflected in the fourgroup subtype formulation presented here. This result was repli cated 15 years later using a large data set from a multisite collaborative study of the genetics of alcoholism (Bucholz et al. in press). Such findings suggest that investigators must be sensitive to contextual factors-such as alcohol use among different age or cultural groups-that may influence the char acteristics of particular subtypes ob tained in research and that may, in turn, have implications for prevention and treatment efforts. Further research in the typology field will both illumi nate such technical pitfalls and uncover the characteristics that most accurately distinguish types of alcoholics from one another. ■